Can I reset my furnace myself?

Cycling the thermostat or the furnace power switch once is reasonable. Repeated resets after a safety lockout are not — the lockout exists to protect you, and repeatedly clearing it can hide a real gas or overheating problem.

How fast can you get to a no-heat call?

No-heat calls are treated as priority. We schedule same-day where the route allows and offer after-hours emergency dispatch when the home has no other heat source.

Does a cold-air furnace always mean an expensive repair?

No. A large share of no-heat calls end with a filter, a flame sensor cleaning, or a control adjustment. We diagnose first and give you a written price before any part is ordered.

Why Your Furnace Is Blowing Cold Air

Section 1

Check the thermostat fan setting first

A thermostat left on FAN instead of AUTO runs the blower continuously, including between heating cycles. Air moves, but it is room temperature or cooler. Switch to AUTO and wait for a full cycle before assuming a mechanical failure. Also confirm the system is set to HEAT and the setpoint is several degrees above the current room temperature.

Related: HVAC service in Greer, SC

Section 2

Airflow restrictions and safety lockouts

A clogged filter or blocked return starves the furnace of airflow. The heat exchanger overheats, the high-limit switch shuts the burners down, and the blower keeps running to cool the unit — which is exactly what cold air from the vents feels like. Replace the filter, open closed supply registers, and clear anything stacked against the return grille.

Section 3

Ignition, flame sensor, and gas supply

Gas furnaces need a clean flame sensor to prove the burner lit. A sensor coated in carbon tells the control board there is no flame, and the furnace shuts down after a few attempts. Igniters crack with age, and a closed gas valve or empty propane tank produces the same symptom. These checks involve live gas and line voltage, so they belong to a technician.

Section 4

Heat pumps behave differently

Many Upstate homes use heat pumps rather than gas furnaces. A heat pump delivers air that feels cool on your hand even when it is heating properly, because supply air runs near body temperature. If the air is genuinely cold, look at defrost mode, a stuck reversing valve, or low refrigerant. We measure the temperature split across the coil rather than guessing by feel.

Frequently asked questions

Can I reset my furnace myself?: Cycling the thermostat or the furnace power switch once is reasonable. Repeated resets after a safety lockout are not — the lockout exists to protect you, and repeatedly clearing it can hide a real gas or overheating problem.
How fast can you get to a no-heat call?: No-heat calls are treated as priority. We schedule same-day where the route allows and offer after-hours emergency dispatch when the home has no other heat source.
Does a cold-air furnace always mean an expensive repair?: No. A large share of no-heat calls end with a filter, a flame sensor cleaning, or a control adjustment. We diagnose first and give you a written price before any part is ordered.

Services mentioned

Heating Repair

Heating and heat pump service when your system is not performing properly.

Furnace Repair

Gas and electric furnace diagnosis, repair, and safety inspection.

Emergency HVAC Repair

Urgent heating and cooling failures handled with fast diagnosis and clear options.

Furnace repair by city

We serve Greenville County, SC and Spartanburg County, SC and Anderson County, SC and Pickens County, SC. Pick your city for local pricing, response times, and scheduling.